Estimation of the Rate of Release of Adrenal 17-Hydroxycorti-Costeroids in the Human Being by the Venous Catheter Technique With a Method for Determining Plasma 17-Hydroxycorticosteroids 1

The importance of the role of the adrenal cortex in protein and carbohydrate metabolism and in adjustments to injury has been well established in experimental animals.Studies of the activity of the adrenal cortex in similar situations in hu- man beings have been handicapped by lack of a direct objective method for estimating the rate of secretion of adrenal cortical hormones in the intact man.Since it seemed possible that the in- travenous catheter technique might be applicable to this problem, attempts were made to estimate the rate of secretion of the adrenal hormones di- rectly by obtaining blood from the left renal vein, proximal to the entrance of the adrenal vein, and multiplying the arterio-venous difference in con- centration of cortical hormones by the renal plasma flow.The method has serious limitations, and, as will be discussed below, is probably not sufficiently accurate to be useful as an experimental clinical tool. ANALYTICAL METHODSAt the time that this project was initiated, no specific method was available for the estimation of adrenal cor- tical steroids in plasma.Attempts were therefore made to use bioassay methods on whole plasma, since it was hoped that this would afford a high degree of specificity, without any danger of loss of hormone during the extrac- tions and manipulations incidental to the use of a chemi- cal assay.The concentration of liver-glycogen-depositing material in human arterial plasma proved to be too small to be detected.For the purposes of the assay, 70 mg. of glucose were dissolved in 1.26 ml. of plasma + 0.14 ml. of ethyl alcohol.This solution was injected subcutaneously in seven 0.2 ml.portions into each adrenalectomized mouse according to the schedule of Venning, Kasmin, and